The aim of the experimental work was to obtain the hollow microspheres alumina, used as fillers in the preparation of insulating coating materials.
As a method of preparation was approached sol-gel technique combined with ion extraction method by emulsified sols. Synthesized gels were calcined at different temperatures and were characterized in order to determine the structure and morphology of oxide microspheres obtained.
The conditions for formation of hollow microspheres were determined. Also it was establish the influence of organic components on the morphology of Al2O3 microspheres, and the influence of technological parameters (sols mixing rate, drying and sintering temperature) on the formation of hollow alumina microspheres
The gel microspheres and hollow microspheres were characterized by using thermogravimetriy analysis, differential thermal analysis, X-ray diffraction, microstructural analysis. XRD results indicated the formation of αAl2O3 at 12000C, and optical and scanning electronic microscopy confirmed the cavitary morphology of the gel calcined.